[dhcp] Split PXE menuing code out of dhcp.c

The DHCP client code now implements only the mechanism of the DHCP and
PXE Boot Server protocols.  Boot Server Discovery can be initiated
manually using the "pxebs" command.  The menuing code is separated out
into a user-level function on a par with boot_root_path(), and is
entered in preference to a normal filename boot if the DHCP vendor
class is "PXEClient" and the PXE boot menu option exists.

1 files changed, 24 insertions, 25 deletions

diff --git a/src/net/fakedhcp.c b/src/net/fakedhcp.c
index 2fb08c69b..0518789c3 100644
--- a/src/net/fakedhcp.c
+++ b/src/net/fakedhcp.c
@@ -108,12 +108,11 @@ static int copy_settings ( struct dhcp_packet *dest,
 int create_fakedhcpdiscover ( struct net_device *netdev,
 			      void *data, size_t max_len ) {
 	struct dhcp_packet dhcppkt;
-	struct in_addr dummy_addr = { 0 };
+	struct in_addr ciaddr = { 0 };
 	int rc;
 
 	if ( ( rc = dhcp_create_request ( &dhcppkt, netdev, DHCPDISCOVER,
-					  dummy_addr, dummy_addr, dummy_addr,
-					  NULL, data, max_len ) ) != 0 ) {
+					  ciaddr, data, max_len ) ) != 0 ) {
 		DBG ( "Could not create DHCPDISCOVER: %s\n",
 		      strerror ( rc ) );
 		return rc;
@@ -138,7 +137,7 @@ int create_fakedhcpack ( struct net_device *netdev,
 	int rc;
 
 	/* Create base DHCPACK packet */
-	if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK, NULL,
+	if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK, NULL, 0,
 					 data, max_len ) ) != 0 ) {
 		DBG ( "Could not create DHCPACK: %s\n", strerror ( rc ) );
 		return rc;
@@ -164,7 +163,7 @@ int create_fakedhcpack ( struct net_device *netdev,
 }
 
 /**
- * Create ProxyDHCPACK packet
+ * Create fake PXE Boot Server ACK packet
  *
  * @v netdev		Network device
  * @v data		Buffer for DHCP packet
@@ -173,43 +172,43 @@ int create_fakedhcpack ( struct net_device *netdev,
  *
  * Used by external code.
  */
-int create_fakeproxydhcpack ( struct net_device *netdev,
-			      void *data, size_t max_len ) {
+int create_fakepxebsack ( struct net_device *netdev,
+			  void *data, size_t max_len ) {
 	struct dhcp_packet dhcppkt;
-	struct settings *settings;
-	struct settings *bs_settings;
+	struct settings *proxy_settings;
+	struct settings *pxebs_settings;
 	int rc;
 
-	/* Identify ProxyDHCP settings */
-	settings = find_settings ( PROXYDHCP_SETTINGS_NAME );
-
-	/* No ProxyDHCP settings => use normal DHCPACK */
-	if ( ! settings )
+	/* Identify available settings */
+	proxy_settings = find_settings ( PROXYDHCP_SETTINGS_NAME );
+	pxebs_settings = find_settings ( PXEBS_SETTINGS_NAME );
+	if ( ( ! proxy_settings ) && ( ! pxebs_settings ) ) {
+		/* No PXE boot server; return the regular DHCPACK */
 		return create_fakedhcpack ( netdev, data, max_len );
+	}
 
 	/* Create base DHCPACK packet */
-	if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK, NULL,
+	if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK, NULL, 0,
 					 data, max_len ) ) != 0 ) {
-		DBG ( "Could not create ProxyDHCPACK: %s\n",
+		DBG ( "Could not create PXE BS ACK: %s\n",
 		      strerror ( rc ) );
 		return rc;
 	}
 
 	/* Merge in ProxyDHCP options */
-	if ( ( rc = copy_settings ( &dhcppkt, settings ) ) != 0 ) {
-		DBG ( "Could not set ProxyDHCPACK settings: %s\n",
+	if ( proxy_settings &&
+	     ( ( rc = copy_settings ( &dhcppkt, proxy_settings ) ) != 0 ) ) {
+		DBG ( "Could not copy ProxyDHCP settings: %s\n",
 		      strerror ( rc ) );
 		return rc;
 	}
 
 	/* Merge in BootServerDHCP options, if present */
-	bs_settings = find_settings ( BSDHCP_SETTINGS_NAME );
-	if ( bs_settings ) {
-		if ( ( rc = copy_settings ( &dhcppkt, bs_settings ) ) != 0 ) {
-			DBG ( "Could not set BootServerDHCPACK settings: "
-			      "%s\n", strerror ( rc ) );
-			return rc;
-		}
+	if ( pxebs_settings &&
+	     ( ( rc = copy_settings ( &dhcppkt, pxebs_settings ) ) != 0 ) ) {
+		DBG ( "Could not copy PXE BS settings: %s\n",
+		      strerror ( rc ) );
+		return rc;
 	}
 
 	return 0;